Rotary steam-engine.



G. MILLER ROTARY STEAM ENGINE. APPLICATION FILED DEC. 21, 1907.

98 1 ,785. Patented Aug. 24, 1909.

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0. MILLER. ROTARY STEAM ENGINE. APPLICATION FILED DEC. 21, 1907.931,785; Patented Aug. 24, 1909.

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IIIIIQ ill! I11] ll 72 34 5/ 239mm 1 8W6 M CHARLES MILLER CHARLESMILLER, OF NEW YORK, N. Y.

ROTARY STEAM-ENGINE.

Specification of Letters Patent.

Application filed December 21, 1907. Serial No. 407,469.

To all whom it may concern:

Be it known that 1, CHARLES MILLER, a citizen of the United States,residing in the city, county, and State of New York, have invented a newand useful Improvement in Rotary Steam-Engines, of which the followingis a specification.

The invention, of which my rotary engine is an embodiment, is designedwith the idea of taking advantage of the many desirable features of thistype of engine such as lack of reciprocating parts, absence of deadcenter, simplicity of arrangement, compactness, etc., while at the sametime avoiding as far as possible its disadvantages.

My invention is directed especially to the construction of a rotaryengine in which the friction of the various moving parts is reduced toan unusual degree. This is a very. important factor in rotary engines asowing to the high speeds under which it has hitherto been necessary tooperate, the amount of friction has been so very great as to be thecause of a very considerable loss of power.

My object is to increase as far as possible the size of the expansionchambers, thus removing the necessity of operating under excessivespeeds.

A further object has been to reduce the pressures on the various slidingparts so as to obviate the excessive friction that is ordinarilyincident to the movement of machine parts at high speeds. This, I haveaccomplished in one instance by balancing one of the rotating elementsin such a way that whenever a certain thrust due to the steam pressureis exerted on one side an equal and opposite thrust is always providedon the opposite side. I have also arranged the journals of the remainingrotating elements so as to remove them as far as possible from theinfluence of the steam pressure, so that although these parts are not soarranged that the steam pressure balances them from opposite sides,nevertheless, the thrust due to the steam pressure thereon is reduced toa minimum, and the parts are allowed to rotate substantially as if theywere not subjected to any force other than that of their own weight. Thevarious remaining details of my structure are such, furthermore, as havebeen found to be conducive to the' production of a maximum of efficiencyin the normal operation of the engine.

In the accompanying drawings: Figure 1 represents a vertical view of myengine with one side plate removed; Fig. 2 is a vertical elevation ofthe engine with the cover for the valve-chamber removed; Fig. 3 is ahorizontal view of the entire engine in section; Fig. at, an insideelevational view of the side-plate appearing in Fig. 2; Fig. 5, asectional View of the same plate taken on line 5-5, Fig. 1; and Fig. 6,a sectional view of the same taken 011 line 66, Fig. 1.

The engine consists of a main casing 1, having two circular transverseopenings 2, 3, to constitute steam expansion chambers and an additionalsmaller circular central opening a intersecting the peripheries of thesteam chamber openings, all of said openings being closed by side-plates5, 6, secured to the main'casing l in any approved manner as by screwsor bolts.

In the outer face of the side-plate 5 is located a valve-chamber 7 whichis closed by a head 8, secured thereto by screws or bolts, having asteam inlet pipe 9 projecting laterally from its center. Located in thesides of the valve chamber are two longitudinal steam ports 10, both ofwhich connect with transverse steam ports 11 and thence with the steamchambers 2, 3. It will be noted that these steam ports are diagonallyoppo site each other. In the sideplate 6 and on the other diagonal arelocated two exhaust ports 12, one for each of the steam chambers.

A rotary valve 13 is situated in the valve chamber 7. This valveconsists of a transverse septum let the ends of which are provided withcylindrically shaped members 15 which are wider and thicker than theseptum I l and adapted to fit closely within the circular valve chamber7. The septum 1a is tight on a central. shaft 16, which extends entirelythrough the main casing l and the side plates 5, 6, being journaled inthe latter. On this shaft within the chamber 4L is secured a rotaryabutment 17 having two opposite cavities 18. The pistons or wings 19, 2Ofit within these cavities though not necessarily tightly as the valve 13operates in such a way as to prevent the escape of steam when thepistons are at this point in the path of their rotation. The pistons 19,20, fit closely within the expansion chambers 2 and 3 where they rotatewith the thin cores 21, 22 carried upon the axles 23, 24, journaled inthe side plates 5, 6. The thin cores 21, 22 are each supported betweentwo of the cylindrical bosses 25, 26, 27, 28 which project from thesurfaces of the side plates Patented Aug. 24, 1909.

5, 6 around the axles 23, 2 1 into the expan sion chambers 23. It willbe noted that the thickness of each core is only a very small proportionof the entire width of the steam chamber in which it is contained, butthat almost the entire width of the chamber is occupied by thecylindrical bosses. The axles 23, 24; and the shaft 16 project throughthe side plate 6 and are provided with gear wheels 29, 30, 31, whichmesh with each other. These gear wheels are all of the same size. One ofthe shafts 23, 24 may be extended to any length desired and furnishedwith a power-pulley (not shown).

In the operation of the device, steam being admitted to pipe 9, itpasses thence'into the valve chamber 7, the septum 14: being sufhcientlythin to allow the free passage of the steam both above and below it.When the rotary valve has uncovered the ports 10 the steam passessimultaneously through these to the two steam expansion chambers 2 andThe valve 13, however, is so placed on the shaft 16 that these ports areuncovered only when the periphery of the abutment 17 is in contact withthe cores 21, 22, so that when the abutment is in the position shown inFig. 1, for example, the steam supply is shut off, ,as in my engine Imake the pistons 01' wings 19, 20 fit only loosely in the cavities 18,thereby avoiding the very great amount of friction that invariablyaccompanies a tight fit between these parts. The valve 13 is furthermoreso arranged on the shaft 16 that the steam is not permitted to enter thesteam chambers until the pistons or wings 19, 20 have passed beyond thesteam inlets 10 as, otherwise, the admission of steam at this point inthe rotation of the pistons would have a tendency to retard rather thanaccelerate their movement. The steam, then, after passing into the steamchambers continues to expand thereby driving the pistons around theiraxes in the direction of the arrows, until they pass beyond the exhaustports 12, at which point the steam is, of course, allowed to exhaust. Asthere are two pistons or wings in each steam chamber it should be notedthat while steam is being admitted to one part of each of the chamberssteam is being exhausted from another portion thereof. Through theagency of the gears 29, 30 and 31 the pistons in the two steam chambersrotate in unison and at the same speed. There is consequently only arolling contact between the rotary abutment. and the axes as all thesehave the same diameter. Power is conveyed from the shaft 23 or the shaft2% and utilized for any purpose desired.

gine as by providing a large space for expansion the speed at which itis necessaryto operate this type of engine to obtain the proper returnor power may be decreased to that extent thereby decreasing the amountof friction and securing a consequent increase of etficiency in theproduction of power.

By arranging the abutment in the middle and admitting the steam to thetwo chambers simultaneously on diametrically opposite sides thereof, andclosing off the steam in the two chambers simultaneously, the forces orside thrusts exerted on the two sides of the abutment are alwaysmaintained equal and opposite. As a consequence, the friction and w aron the journals of the abutment and between the abutment itself and itscasing are reduced to a minimum.

The thickness of the cores'21, 22 has been made very slight so as toreduce theside thrust of the steam on the axles 23 and 24 to an almostnegligible quantity so far as friction and tendency to wear areconcerned.

As has been noted above I have especially constructed my engine with avery loose fit between the rotary abutment and the pistons so as toavoid friction at this point.

Various changes might be made in the minor details and in thsubstitution of equivalents for the important features without departingfrom the spirit of my invention.

What I claim and wish to secure by Letters Patent is:

1. Tn a device of the character described and having a rotary abutmentlocated be tween opposite steam chambers, a rotary piston in each steamchamber said piston comprising opposite wings fixed to a thin core andthe axis of rotation of said piston being perpendicular to said core,substantially as and for the purpose described.

2. In a device of the character described and having a rotary abutmentlocated between opposite steam chambers, a rotary piston in each steamchamber said piston comprising opposite wings fixed to a thin core, theaxis of rotation of said piston being perpendicular to said core andsaid core being adapted to rotate with its edge rolling upon the headsof said abutment, substantially as and for the purpose described.

8. In a device of the character described and having a rotary abutmentlocated besteam supply, said valve being attached to the abutment androtating therewith in a cylindrical valve chamber with which said Valvecontacts only at the cylindrical wall thereof whereby steam surroundssaid valve except at its ends and valve friction is diminished,substantially as and for the purpose described.

5. In a rotary engine comprising a central abutment rotating betweenopposite steam chambers, a valve adapted to control the steam supply,said valve comprising a thin septum fixed transversely to the abutmentaxis and inclosed in a valve chamber with free space on all sides ofsaid septum eX- cept at the ends thereof which are formed as segments ofa cylinder and closely engage cylindrical walls of the valve chamber,said walls being provided with opposite ports which are adapted to becyclically opened and closed as the valve rotates, substantially as andfor the purpose described.

6. A rotary engine comprising a casing inclosing opposite annular steamchambers, a central steam chamber in which is a twolobed rotaryabutment, a piston in each annular steam chamber, comprising twoopposite Wings fixed to a thin core, said wings being adapted tocooperate with said abutment and the lobes of said abutment beingadapted to roll upon the edges of said cores, and a valve upon theabutment shaft, said valve bein adapted to control the steam supply andmoving within a cylindrical valve chamber with which said valve contactsonly at the cylindrical wall thereof, substantially as and for thepurpose described.

In testimony whereof, I have hereunto affixed my name in the presence oftwo subscribing witnesses.

CHARLES MILLER.

Witnesses:

ARTHUR WRIGHT, JOHN A. KEHLENBECK.

